Field of the Invention
The present invention relates to a nerve cuff stimulation electrode, a control device for a Vagus Nerve Stimulation (VNS) system, and a VNS system.
Description of the Background Art
Vagus Nerve Stimulation (VNS) systems and methods are inter alia disclosed in U.S. Pat. No. 8,401,640, US 2013/0184773 and U.S. Pat. No. 8,473,068.
Cervical VNS may be used for the treatment of Congestive Heart Failure (CHF).
Conventional chronic implantable apparatuses for VNS for the treatment of CHF generally involve implanting a cervical nerve cuff electrode for stimulation that connects via wires to an Implantable Pulse Generator (IPG) in a patient's chest. A standard pacemaker sensing lead in the ventricle has been disclosed for the purpose of synchronous delivery of VNS pulses in the cardiac refractory period. This sensing lead allows for certain cardiac timing monitoring. However, there is a need for an improved VNS system.
Chronic implantable VNS for CHF apparatuses in the prior art generally lack monitoring capabilities for disease progression, or these are limited to cardiac timing and transthoracic impedance measurements which require leads in the heart. Since the targeted CHF patient population may require implantation of an implantable cardioverter/defibrillator to prevent sudden cardiac death or another cardiac rhythm management device, it is preferred to avoid adding leads in the heart for the purpose of delivering VNS therapy. Apparatuses in the prior art lack, in particular, the capability of measuring arterial or venous pressure waveforms, which are critical parameters in the assessment of complications related to CHF. Patient sleeping angles, as well as OSA-related parameters, can also give extra diagnostics information in this patient population. VNS for CHF apparatuses in the prior art lack these measurement capabilities as well.
Prior art apparatuses also suffer from limited lifetime, since they are powered from a primary battery, which requires a revision surgery to replace the IPG once its battery depletes. Rechargeable and inductively-powered IPGs, and wirelessly-powered nerve cuff electrodes with embedded electronics, have been proposed in prior art for other VNS therapies (e.g. epilepsy, obesity), but are not suitable for adaptation to VNS for CHF due to patience-compliance issues. A VNS for CHF apparatus cannot rely on the patient to provide power to deliver therapy.